1. Field of the Invention
The present invention relates generally to semi-conductor module test apparatus using so called burn-in boards. More particularly, the present invention is directed to a high current, open/short power connector especially useful with such semiconductor module test and burn-in apparatus. An apparatus provided with the high power, open/short connector of the present invention can easily couple selected devices on the burn-in-board to significantly higher power levels.
2. Background of the Invention
As is well known to the art, integrated circuits modules have a number of signal interface points or pins, herein after referred to as input/output pins, that are used to transfer data, in the form of electrical signals, into or out of the integrated circuits modules. During operation a select number of these pins are used to introduce the necessary functions such as the circuit clocks, test modes, test control data, and etc. to the integrated circuit while other signal interface pins are used to transfer data into and out of the data storage circuits contained in the integrated circuit. These pins are arranged in a particular pattern called a footprint.
One test operation required during the manufacture of such modules is the so called burn-in test performed by placing the modules to be tested on burn-in-boards (BIBs) and powering up the modules while simultaneously heating the burn-in-boards in an oven. Typically the oven are designed to accommodate sixteen to thirty-two burn-in-boards. Each burn-in-board is typically comprised of a board having a plurality of sockets or power planes. Each such socket is adapted to accept therein the footprint of the module to be tested. Each such socket or power plane is thus designed to accommodate a specific type of semi-conductor integrated circuit and each burn-in-board is designed such that when it is placed in the burn-in oven each socket or power plane is electrically connected to suitable signal lines and power sources such each module on the burn-in-board can be properly energized. Presently, many semiconductor modules having a particular footprint are tested in these burn-in boards and draw less than 75 amperes of current from the power sources during this burn-in process. Other modules having the same footprint will require a current draw in excess of 75 amperes. Because of the operating characteristics of the burn-in ovens, if a module being tested exceeds the 75 amperes draw they will be considered failures due to over current conditions even though they are not failures. For this reason the higher current drawing modules cannot use the same power planes as the lower current drawing modules and vice versa. Thus, at present, each type of module depending on its current draw requires its own burn-in-board. For this reason the prior art required a multiplicity of burn-in-boards for each board was designed to accommodate a specific module and current draw. Thus a large number of burn-in-boards is required and this multiplicity of boards results in increased capital costs as well as costs due to the need for storage space and maintenance for the additional boards. All of these factors increase the cost of testing the modules. Further there is always a possibility that the wrong power plane could be used resulting in erroneous results which require either retesting or scrapping of the modules so tested. Thus there are compelling economic reasons to be able to easily convert a burn-in-boards power plane current carrying capacity to different levels.
Accordingly the present invention is designed to circumvent these difficulties and does so by providing each burn-in-board with a means for altering the applied current levels of selected ones of the power planes between current desired levels.